California may become the first state to ban "conversion" therapy for gay and lesbian teens if a bill, spearheaded by Democratic State Sen. Ted Lieu, passes on the senate floor. The bill passed its final committee vote Tuesday.

The bill would make it illegal for psychologists in the state of California to provide gay and lesbian conversion or reorientation therapy to teens. The controversial conversion therapy, sometimes also known as reparative therapy, attempts to change the sexual orientation of a person from homosexual (or bisexual) to heterosexual.

The bill would also require adults who submit to the therapy to sign a release saying they know what they're getting into.

"This therapy can be dangerous," Lieu said. He and supporters of the bill said conversion counseling is ineffective, can cause severe depression and guilt, and can even lead to suicide.

The American Psychological Association defines the type of therapy as based upon "the assumption that homosexuality per se is a mental disorder or based upon the a priori assumption that a patient should change his/her sexual homosexual orientation."

The California bill quotes a 2009 APA report that defines conversion therapy as "unlikely to be successful and involves some risk of harm." The APA did not take a position on the California bill.

Nevertheless, Clinton W. Anderson, director of the APA's Lesbian, Gay, Bisexual and Transgender Concerns Office, told ABCNews.com, "Because APA doesn't see same-sex sexual orientation as being in any essential way different from other sexual orientations, we do not believe there is any psychological reason why people should change, and we believe those individuals and organizations that still promote such therapy or other methods of change are contributing to a negative social climate for lesbian, gay, and bisexual people, especially young people."

Alan Chambers, president of Exodus International, has been a proponent of conversion therapy. Exodus International says it offers "grace and truth to a world impacted by homosexuality."

In a 2011 interview with ABCNews.com, Chambers said, "Does counseling help people who are struggling to live through the filter of the faith over their sexuality? It definitely, absolutely does."

Chambers compared homosexuality with obesity.

"We can look at other organizations who help people dealing with other life struggles," he said. "For instance, Weight Watchers, which has tremendously benefited my life. Should we go after Weight Watchers and tell them, 'Don't say that there's anything beyond obesity,' for people who are struggling with obesity and want an alternative to that?"

Dr. Carol Bernstein, associate professor of psychiatry at NYU Langone Medical Center and past president of the American Psychiatry Association, told ABCNews.com conversion therapy has "no scientific basis whatsoever." She said she has never known a psychiatrist to offer it and has never known a patient to be involved in it.

"Being gay or lesbian is not a disorder," Binks said. "While at times people need therapy to better understand their sexuality and to assist them in considering issues of sexuality in the context of their lives, 'conversion' therapies, as the name implies, too often tend to start from a presumption that it is wrong to be gay and that the only goal is to change that; which is not a helpful therapeutic approach."

A San Francisco man, Peter Drake, testified at the California Senate Judiciary committee hearing on Tuesday that he had undergone conversion therapy treatment for three years.

"I have a personal, painful experience with the harm that can be done by reparative therapy," Drake was quoted as saying by the San Francisco Chronicle. "My depression worsened during the treatment, and there was no change in my sexual orientation... This is a form of medical malpractice, with practitioners who make claims about healing something that is not an illness."

Psychologists and psychiatrists who are practicing such techniques usually belong to religiously-affiliated groups, said Dr. Aron Janssen, clinical director of the Gender and Sexuality Service at NYU Child Studies Center. Conservative groups say it's important for families to have access to such "treatments" for their children and teens, but trying to change something that is not an illness is both ineffective and unethical, Janssen said.

"The main concern I have here is that those who are exposed to these therapies are mostly children and adolescents and they can't consent for their own treatment," said Janssen. "Most of these parents think they're doing right by their children, but it's a harmful treatment and they're exposed to dangerous methods that have negative outcomes on self-esteem, depressive symptoms and identity consolidation."

"Whether or not this bill passes, it's important that this discussion happens," said Janssen. "It lets people know that sexual orientation is not something that people choose or change, and exposing children and adolescents to the idea that who you are is not good enough is something that contributes to an overall negative psychological long-term outcome."